Flying wing



Dec. 9, 1947. R. E. DQWD FLYING WING Filed Nov. 16, 1944 IZIZ/EENTOR. d 0 ,DOZZJ Patented Dec. 9, 1947 UNITED STATES PATENTOFFICE\ 2,432,297 FLYING WING Raymond Dowd, Chicago, Ill. Apelication November 16, 1944,:Serial No. 563,707

6 Claims.

flmislih ention relates to teiile e airplane 9r flyin wines. that maybe e t er ehdexs e p wer driven types, and me fer its prih pal object he nnexzisihnt of. ain tw eedimprevesi d v-v ee thi kind.

It ise Qhject .ef. he e ehtion 'te pmhiee a flyin Wi ethat 135 511 3 menewereb e yet pos esses great inheherxt stability.

Anothe ebje t ef the is to pne is e IatemLstabi-Iity end centrel in a 'fiy he Wine t ru theme. ore comb nation of .siih s zels en h eti-ve win tipeeetiens, vc xme eirxe teme d a mint loc-atedio iwelfidly f win ;i. l,e;. .bher abieet o the ihventie i o 1 1 videefi he Wine that may he m de eheen y, with ut .seer iiei-neinheneht tehmty e meeeh ere i ity- Sti l enether. ob e 9f the h emien i to vRhe idea fl n wine nce eeeretine theteeel ee nti that. beh ed a ltey er en d en em h ve y- Further obj s of the inven ion net sp ci ca ly men ie ed, her i eR Ww He p the eet ile e c ipfionend cla m whic tel-10W rei en e being made to the eeeempanyine drawings ;i;; which a preferred embodiment of the invention is ehow hy wa pfexemple in Whieh:

,Eieure l isle pla n View of the flying Figuneg is elevational View from he. front or eadin ed e pith w ne;

F ur 3 is eress e c or e V e tekensu stent a lyt al he line fit-: Q Eieu e Lionel;- me 1 h the. eiir on of th .e Ws;

Figure 4 is a View milar to, fieu et tshewine a modified form of construction .ffieune *5 is V w/sim 0 Figu 3. .eh wiee a kite string att hed;

figure is e ew-e mi a to F gu e with a rubber, m nd driven propeller atttached.

IIeiHe a rplanes, r flying wines es th y re usually cal ed, have b en th sub ;o 1 1 1214 RIiQr eoneiderationho h ch I am are, o for use as lead teatr in ai plan s and e de is, and also as Qy Such D ier art d v p e ts have mployed la era ly w pt in 0 ,d es re a.s they a u ua ly ca11edto sz iev eater s ili y, an h e als emplqye ,neg t ve twine, p se tions ueuel eemhined Withradi- Cally swept back W e fo pu qpese- E e line f att ment of th negat v Wi e t x tion to the center section of the Wing has been parallel to etm eientl ne for t e hi the e p ior art, d velopmen sln e tiably vent ee -eqm ol .eur a es both fixed an taqjuetable, have been employed to produce lateral stabili ty and 2 mtml, endhe r sep seeh hesepeen edihe d w immhe he yefl ine ehelseres ht w h e213 e thin the vhich lateral steel-L quipmen o .eth ew ee we. t e eeme h ie t's" ef th de ie elie. tl- 2 1: ee 'ven e e re nte orpn seu ez oee en Qithe h m. 1 iseprefereb t ,ehe eeee helle tee eezthat h 1 eme e pres u e end en e eie 'ev t c 41 a Y m nt e ehnatel 27 91.39 he e of the; we mm-th fleedi-ne ti 1 th I m e n o th me ia lineemedme between the edges.

The simp e t io zm te which t y re ent tion may be a p ied i e Wende hi h maybe formed irqm elshee 'Qi m n etifie m ia -.su e ii -me d b n ee erend 1 o 9 nme and prqe my aeiusted; e h h y eme eet hip h vi g ee r nt e lit l nd hieh maneuverabi t i mg llfi fi zan 'tb toyis gap 19 ilexeculti e m w m n uver he z to e trappesible !in'toys qof this kind. Thendevipe meyjeleo be. produced from r hql ded pqlp 91: ma .be mzige x m e al hee o q hlious mate ie e ply-weed as desired. Bower be epe e to p epe je thru the usua mh str nds mo r or i h ase of a l rge Mame-bye m niatu e eese irl e engine and the ship flown the same gs a gull si z e ship w t ipt for QQIltIol iron; within the ship.

(Re e in now to the .drew nes n me e d tail, wherein the inventi is illustrated in con neet on ith a fl i mm y y .Q example, it wil l loe seen in the Figures 1, 23nd 3, in its'eimplest form the toy may co nsietof a sheet of a ir y h a y tone-h fib ous me a lt c a a twent t our poum bond fie ded lene hwi eq en of its edges over and .oyeponitself until approxime el n -h l the h tli di p ed in th old gur which i lded-ove no t px ma be secured o th tma n s etiqn 0f the heet n an p efer ed m ner. 1 as .by Wi e ,Stenles 3,

or by gluing. While stapling or gluing is preferable, it is not necessary, as the stiffness of the stock will hold the folds in place fairly well and an unfastened fold may be used. This foldedover portion forms the front or leading edge of the wing and loads the wing to insure the desired center of gravity location of the wing will coincide with the center of pressure of the wing in normal flight. As shown, the wing is rectangular in shape, which is preferable when formed from sheet stock as described. However, if desired, the chord of the wing may be decreased toward tip sections to form the usual tapered wing, and the wing tips may be suitably rounded.

The wing so formed is bent on its median line 4 so that the sections 5 of the wing adjacent thereto extend upwardly at an angle of approximately ten degrees from a horizontal plane thru the median line 4, giving this portion of the wing a positive dihedral. At the point on the wing indicated by reference 8 the positive dihedral changes to a negative dihedral as well as negative angle of incidence occasioned by the angularity of the line of change reference 8.

A reinforcing and launching tab 6 may be secured to the under side of the wing along the median line 3, and at the leading edge of the Wing in any preferred manner--such as by gluing. This tab may carry a downwardly depending portion 1, which is employed in launching the wing, as will presently appear. The tab has no aerodynamic function since the wing flies equally as well without this tab.

The wing sections 5 are bent downwardly along lines 8, which lines 8 if extended would intersect the median line 4 extended, at a point three or more chord lengths ahead of the leading edge of the wingthat is, point of intersection is preferably three or more times as far from the leading edge of the wing as is the trailing edge of the wing.

The negative angle wing tip sections 9 so formed terminate approximately on the horizontal plane thru the median line 4 at the leading edge of the wing. These wing tip sections 9 converging at a point ahead of the wing and at the same time below the median line of the wing at the leading edge, produce no appreciable loss of lifting efficiency of the wing but do increase the maneuverability and inherent stability of the wing.

While the location of the point of convergence of the tip sections at three or more chord lengths ahead of the wing is preferable, it may be varied within the teachings of the invention. If the distance is increased the sharpness of the angle is decreased and the amount of stability and control obtained thru the wing tips is decreased. If the distance is decreased the stability and control obtained is increased, but the drag of the sections is increased and the efiiciency of the wing impaired, The three chord minimum distance has been found to strike a desirable balance between these efiects.

As shown in the drawings, the area of the wing tip sections is approximately one-half the area of the main wing, a proportion which has been found to be satisfactory. A greater or lesser proportion of the total wing area may be incorporated in the wing tips within the teachings of the invention. Generally speaking, the greater the wing tip area the smaller the angle of convergence necessary to produce a given effect and with a larger tip area the point of convergence may be moved farther ahead of the wing without loss of lateral stability and control.

The trailing edge [0 of the wing is preferably bent slightly upward along a line II that is parallel to the leading edge of the wing and extends thru the wing sections 5. In the drawings the angle of upward bend of the trailing edge :c has been exaggerated somewhat for clarity. This angle may be varied to increase or decrease the downward thrust on the trailing edge of the wing produced by tne flow of air on section lit and thereby decrease 0r increase the angle of glide of the wing. This same means is employed to bring the center of pressure into coincidence with the center of gravity under normal flight conditions.

When launched in a substantially horizontal position the properly adjusted wing has a small angle of attack, possibly one or two degrees, and will descend at a fairly fiat angle of glide so that the wing travels a considerable distance before landing. As is well understood by those in the art that the center of pressure in a wing of this type usually is approximately one-third of the distance back from tne leading edge, and with the center of gravity located slightly forwardly of this usual center of pressure, the ship is nose heavy and has a steep angle of glide. This tendency is corrected by the downward thrust on the trailing edge of the wing occasioned by tne force of air on section in, which brings the center of pressure into coincidence with the center of gravity as well as improving the longitudinal stability. By proper adjustment of the angle of this section it this force can be controlled and the angle of glide can be set to any desired value.

With the wing properly formed and adjusted as above the center of gravity and the center of pressure of the wing both fall on the median line and when released in a horizontal position, the wing glides in a straight line. If it fails to do this, the negative angle of one of the tip sections 9 can be increased to compensate for any unbalance in the structure and this adjustment varied until the wing glides in a straight line.

Figures 1 and 2 show the wing symmetrical in all respects but it should be pointed out that a convenient directional control can be exercised by the simple expedient of changing the angle of the outer sections of the wing as indicated by the dotted lines 9 Figure 2. The increase of the angle decreases the lift and increases the drag on the side of the change thereby causing a turning effect for the Whole wing without the use of conventional ailerons or rudders. Likewise if one tip angle is increased and the other decreased the effect is more pronounced.

When properly adjusted, if the wing is released at an upward angle and with considerable force,it will fiy in a vertical loop until its speed is reduced to the point at which it will glide in a straight line. When properly adjusted and launched, the wing will make a large loop and then a smaller loop beiore straightening out into its straight angle glide. Launching for such maneuvers can best be accomplished by the use of a catapult such as-for examplethe catapult shown in my prior Patent 1,652,519, issued December 13, 1927.

When properly adjusted and launched in vertical or steep bank, the wing will glide in a circular path returning to a point at or near the point of launching. When launched with a catapult, the wing may negotiat several complete circles before losing its flying speed. As will be apparent to one skilled in the art, the radius of the circle thru which the wing thus flies can be adjusted by varying the angle of upturn of the trailing edge I? of the wing.

.If desired,the launching tab 1 may beperforated at a. point. [2, which is coincident wither veryslightly in advance of the center of gravity of the wing and athread or string attached to the wing thru its perforation. The string may be attached to a rod or. pole such as, for example, a fishing pole, which is moved to pull the wing thru the air, preferably in a generally circular path. With a little practic in manipulation, the wing can be made to execute a large variety of dives and glides under these conditions.

The tab 1 may also be perforated at a point I 3, Figure 5, which is near-the leading edge-of the wing and well in advance of the center of pressure. 7 A kite string I4 may be attached at this point and with the wing in proper adjustment, it can:be flown as a kite in stableflight without loading the'trailing edge with .a conventional tall as has been necessary heretofore in models of this kind to stabilize the flight of the kite. The inherent stability of the properly adjusted wing is so great that the use of a tail'has been found unnecessary, in quiet air. However, under conditions of. agusty or highly variable wind velocity a drag lineextending rearwardly from the trailing edge prevents the wing from gliding upwind during lulls in the wind. This drag line serves to decrease the gliding angle and causes the wing to settle rather than to advance upwind.

While the flying wing involving the teachings of the present invention can be formed by rolling up a sheet of paper in the manner just described, the model so formed can be used repeatedly before the folds become so weakened that the wing will quickly get out of adjustment, it is not necessary that the wing be constructed in this manner. As will be shown in Figure 3, the wing may be formed of a fibrous material and stiffening along its leading edge by greater accumulation of that material at this point. Fibrous material may be in the form of a sheet of light cardboard and the accumulations formed by pasting or gluing an additional piece of cardboard along the leading edge or the fibrous material may be pulp and the wing molded therefrom in the usual manner. The molded pulp wing, in which the wing tip sections and trailing edge section I!) are molded into the model, should stand more usage than when a wing is formed of paper in the foregoing manner. The teachings of the invention may also be applied to conventionally constructed wings having spars, beam ribs, etc., located within the airfoil, this type of construction being preferable in the larger power driven models.

In Figure 6 I have illustrated the manner in which power may be applied to the wing hereinbefore described. The wing in this case will be shaped as before except for the launching tab 1 which will be replaced by a longer and stronger stiffening means l5, located on the underside of the wing at the median line. Adjacent the leading edge of the wing is a bearing it, which carries the propeller shaft ll, to which is secured the propeller l8. Near the trailing edge of the wing, stiffening means I5 carries a hook H) to which one end of a rubber strand is secured, theother end being secured to the propeller shaft IT. The Weight of the reinforcement at the leading edge of the wing is decreased since the propeller and shaft extending forwardly of the wing will provide suflicient ballast to bring the center of gravity into coincidence with the center of pressure of the wing. The angle of upward turn of the trailing section In of the wing can b varied so that when the airplane so formed is flown, it will fly at the desired angle. Because of the greater wing to which power devices shown in Eigurefi are; applied. is formed in this manner. Power devices'known to those skilled in the art may require larger-wings than can be readily formed of pulp and the use of a wing constructedwith ribs and spars covered with a skin is contemplated insuch cases.

In the'foregoing description, the principlesof the invention have been applied-to a model or toy wing. Such wings may be cheaply constructed for sale as a. toy or advertising novelty. While the invention lends itself well to such use, it may also be applied to larger wings including full size airplanes and. gliders and I am not to bev limited by the illustration and description shown by way of example. The teachings of the invention produce a flying wing. having great inherent stability, a high degree of maneuverability and by adjusting the angle of the wing tips and trailing edge, adequate control is obtained. In a full size ship, theseadjustments can be made under the control of an operator within the ship while it is in flight.

Having thus complied with the statutes and shown and. described a preferred embodiment of my invention, what I consider new and desire to have protected by Letters Patent is pointed out in the appended claims.

What is claimed is:

1. A flying wing substantially rectangular in plan form, a main central section of said wing of positive dihedral and embracing approximately two-thirds of the total surface area of the wing, and wing tips of negative dihedral rigidly fixed to said main section along lines converging toward a point substantially three chord lengths ahead of the wing.

2. A flying wing substantially rectangular in plan form, a main central section of said wing of positive dihedral and embracing approximately two-third of the total surface area of the wing, wing tips of negative dihedral rigidly flxed to said main section along lines converging toward a point substantially three chord lengths ahead of the leading edge of said wing, said leading edge in elevation rising from the central point of said main section in a wide angle V and said tip sections extending downwardly and outwardly from said main section and terminating in a horizontal plane through the center of said main section.

3. A flying wing substantially rectangular in plan form comprising, a main central section of said wing of positive dihedral and embracing approximately two-third of the total surface area of the wing, wing tips of negative dihedral rigidly fixed to said main section along lines converging toward a point substantially three chord lengths ahead of the leading edge of the wing, and an upturned trailing edge on said main section.

4. A flying wingsubstantiallyrectangularinplan .form comprising, a main central section of said wing of positive dihedral and embracing approximately two-thirds of the total surface area of the wing, wing tips of negative dihedral rigidly fixed to said main section along lines converging toward a point substantially three chord lengths ahead of the leading edge of the wing, and means on the leading edges of said main and tip sections for stiffening the same.

5. A flying wing substantially rectangular in plan form comprising, a main central section of positive dihedral and. embracing approximately two-thirds of the total area of the wing, wing tip sections [of negative dihedral having approximately one-third of the total area of the wing and rigidly fixed to the main sections along lines converging toward a point substantially. three chord lengths ahead of the leading edge of the wing, means on the leading edge stifiening the main and tip sections thereof, said means being straight in plan form and extending from tip to tip of the Wing, and an upturned trailing edge on the main section of said wing.

6. A flying wing substantially rectangular in plan form formed of fibrous material thick enough to retain its shape, comprising a main central section of positive dihedral and embracing approximately two-thirds of the total area of the wing, wing tip sections of negative dihedral having approximatley one-third of the total'area of the wing and rigidly fixed to the main section along lines converging toward a point substantially three chord lengths ahead of the leading edge of the wing, an upturned trailing edge on said main section for controlling the Wing in flight, and a launching tab secured to the underside of said main section along the median line thereof and adjacent the leading edge and de- 9 pending therefrom, there being a perforation in said launching tab ahead of and below the center of gravity of the wing and through which a string may be attached to permit flying the wing as a kite.

RAYMOND E. DOWD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

